Antimicrobial composition

ABSTRACT

There is disclosed an antimicrobial composition that may be used in the treatment of diseases and conditions associated with farm animals and livestock. The composition may also be utilized as an inhibitor of microbial growth on crops, plants or foodstuffs, such as grains and the like. The composition comprises an antimicrobially effective amount of clove bud oil, eucalyptus oil, lavender oil, tea tree and orange oil but may be diluted with water prior to application.

The present invention is concerned with an antimicrobial compositionand, in particular, with an antimicrobial composition which isparticularly useful in treating diseases and conditions associated withfarm animals or livestock and which can also be utilised as an inhibitorof microbial growth on crops, plants or other foodstuffs.

There are many microbial diseases or, conditions which affect livestockof one type or another. Of particular importance are those conditionswhich can result or contribute to lameness or even death of an animal.Examples of such conditions include Contagious Pustular Dermatitis (Orf)in sheep, footrot in sheep and goats, in addition to foul of the footand digital dermatitis in cattle. Orf is a virus which grows on thesurface layers of the skin and in the mucous membrane of the mouth andnose. It penetrates through small abrasions in the skin. Even very minorgrazes allow the virus to enter. It is a painful and disfiguring diseaseof sheep and goats and causes much distress to affected ewes and lambswhich may result in death. Normally, when Orf occurs in individualanimals, the entire flock should be treated.

Footrot is also an infectious disease of livestock including sheep,goats or cattle and it is spread from animal to animal via pasturecontaining bacteria from the feet of infected animals. Footrot is causedby two different bacteria—Fusobacterium necrophorum (found whereversheep are found) and Bacteroides nodosus of which there are manydifferent strains. Some cause a virulent form of footrot whilst othersare less invasive and are termed intermediate or benign, although thelatter term is misleading because it still causes considerable pain andlameness.

Digital dermatitis on the other hand occurs in cattle and is thought tobe caused by the bacteria Bacteriodes or Treponema but this has not yetbeen completely established. Other notable conditions include sandcracksand mud fever.

Conditions of the hoof or foot of the animal are normally treated eitherby using antibiotics or chemical treatment baths. Orf, however, is notsusceptible to antibiotics being a viral disease. A number ofproprietary products claim to effect a cure, but there is no evidence tosupport these claims. Within a few weeks the disease can in some casesclear up on its own and all that can reasonably be done is to aim toreduce the risk of secondary bacterial infection with the use of topicalantibiotic creams powders or aerosols. In serious cases antibiotics maybe necessary. Vaccines are available but can only be used in flockswhere the disease has occurred previously since it is an attenuatedvirus. Those that are available do not confer a long lasting immunity.

As regards the diseases of the hoof of the animal, foot treatmentscurrently being used in foot baths include various chemicals such as:

-   -   (i) Formalin which is used in dilution of around 3% (1:30 parts        water). However, this compound is painful to broken skin and        stronger solutions can cause scald or severe cracking of skin.        The product must be fresh, as it is ineffective if there is        organic matter in the solution. Furthermore, it gives off toxic        fumes and cannot be used indoors. It is corrosive and toxic;    -   (ii) zinc sulphates which are more expensive and require a        lengthy stand in time of between 30–60 minutes. The product also        requires a large foot bath;    -   (iii) organic acids normally diluted 1:50 parts water. They are        generally of a very low pH and hence very acidic. They can be        damagingly painful to the animal and corrosive to tissue.        Organic acids are completely unselective in their treatment;    -   (iv) copper sulphate: this is widely used and is very toxic to        sheep. It stains the fleece and is corrosive to metal and        poisonous to fish.

All of the above products present serious problems of disposal and ofpain for the animal. Therefore there exists a need for improvedtreatments for treating or alleviating many microbial diseases oflivestock which are not only less expensive than those currentlyavailable but which include non-toxic ingredients which are non-painfulto the animal being treated and which are safe to the environment andthe user alike.

Similarly, microbial growth is a major cause of spoilage of many storedcrops and of plants causing diseases including, for example, moulds andrusts and mildew. Many of these diseases are significant inhorticultural systems.

Therefore, according to a first aspect of the invention there isprovided an antimicrobial composition comprising an antimicrobiallyeffective amount of clove bud oil, eucalyptus oil, lavender oil, teatree oil and orange oil. The formulation has been found to beparticularly effective in treating diseases associated withlivestock/farm animals and especially those conditions such as Orf orringworm and those affecting the foot or hoof of the animal. Thecomposition has been found to be extremely effective in treating thosediseases-caused by a viral, fungicidal or bacterial agent.

Not only has the composition been found to be useful in treating variousmicrobial related animal diseases, but it has also been found that thecomposition is versatile enough in terms of its antimicrobial action tobe effective against microbial diseases in plants and yet is sensitiveenough so as not to kill the plants or crop. The composition istherefore particularly broad spectrum in its mode of action and can beused for treating many types of such conditions. Livestock diseaseswhich are most notably dealt with include Contagious Pustular Dermatitisin sheep (otherwise known as Orf) scald and fibromas, footrot in sheep,cattle and goats in addition to digital dermatitis and foul of the footin cattle. Mud fever, especially occurring in horses is alsoparticularly infectious, and this is also advantageously dealt with bythe composition of the invention. Other diseases in crops and plantswhich are most notably treated include mildew, mould growth, rusts, leafspots and such like.

The formulation is, advantageously, based on a unique blend of essentialoils, all of which are safe to use and which can be disposed ofeffectively. Neither the Council of Europe's Committee of Experts onflavouring substances nor any other European Committee has recommendedlimits on the use of these ingredients. Similarly, each of theingredients has been evaluated by the US Flavouring ExtractManufacturers' Association (FEMA) who have classified them as GRAS(generally recognised as safe).

Preferably, the composition comprises approximately by volume, 16–36%clove bud oil, 34–54% eucalyptus oil, 3.5–13.5% lavender oil, 2–6% teatree oil, and 7.5–27.5% orange oil. When the composition is forapplication to animals or livestock it, preferably, includes athickening agent which allows it to adhere better to the animal.Suitable thickening agents include, for example, a gelling agent, butpreferably comprises lanolin or its derivates, including lanolin oil,lanolin wax, lanolin alcohols, lanolin fatty acids, isopropyl lanolateacetylated lanolin, acetylated lanolin alcohols, lanolin alcohollinoleate, and lanolin alcohol riconoleate. In an even preferredembodiment the composition is further diluted with water. Such acomposition preferably comprises a surfactant. In this aspect thecomposition comprises 5–15% clove bud oil, 10–23.5% eucalyptus oil, 1–6%lavender oil, 0.5–2.5% tea tree oil, 3–9.5% orange oil, 0.5–2.5%lanolin, 0.5–2.0% surfactant and 40–80% water. The composition may beeven further diluted prior to application depending on the nature andseverity of the condition or disease being treated.

As aforementioned the compositions according to the invention are alsoparticularly useful in treating microbial diseases of livestock andparticularly those of the foot or hoof of an animal, and particularlythose conditions associated with a bacterial, viral or fungicidal agent.For treating these types of diseases the composition according to theinvention, may be provided in the form of a foot bath. However, thecomposition may also be applied in any other suitable formulation, suchas a cream or as a spray or aerosol for direct application to theinfected area or area to be treated. The application of the compositionto the animal in question can also confer a preventative or prophylacticeffect as it can prevent secondary infection of conditions such assandcracks or fissures which can often develop in livestock and whichfrequently become infected.

Providing the composition in the form of a spray as opposed to a footbath when the composition is for application to a livestock animaloffers significant advantages as the composition is applied directly tothe affected area. As aforementioned, the properties of the compositionare such that there is no pain or discomfort to the animal when thecomposition is applied either by means of a foot bath or a direct spray.In fact the composition when applied to the affected area advantageouslyconfers a soothing affect to the animal.

The composition may be formulated with conventional propellants fordispersing as aerosols from conventional pressurised containers butpreferably a non-propellant based system is used, such as a trigger pumpspray bottle to produce an aerosol using the pump mechanism which buildsthe necessary pressure to produce the aerosol.

As is known, oil of eucalyptus is obtained from various species ofeucalyptus and the resulting oils do not possess a uniform analysis. Itis believed, however, that the properties of the eucalyptus oil used inthe formulation according to the present invention are not dependent ona particular source of oil of eucalyptus and one may use oil derivedfrom Eucalyptus globulus and/or Eucalyptus dives. Eucalyptus oil is richin cineole and desirably eucalyptus oil according to the inventioncomprises cineole and preferably 1–8 cineole in an amount of fromapproximately 35 to 90% by volume.

In another aspect, there is also provided a composition according to theinvention for use in controlling or alleviating microbial diseases,which in one embodiment may be associated with farm animals orlivestock. Particularly preferred conditions to be treated are thoseassociated with the hoof of ungulate animals. As aforementioned, thecomposition of the invention is particularly advantageous in treatingbacterial, viral or fungicidal diseases or conditions, such as footrot,Orf, foul of the foot and digital dermatitis. However, it has also beensurprisingly found that the composition is of broader spectrum beingactive against not only those diseases mentioned above and specified inthe following examples, but also in treating ringworm in livestockanimals such as cattle. The composition may also be adapted for internaladministration to the animal for use as a wormer, for example. Asaforementioned, the composition can also be used to treat for examplemould in crops which are being stored, for example, in treating mildewor rust or leaf spots on plants or other similar conditions such asmoulds, rusts or mildew, including white blister, powdery mildew, downymildew, grey mould/botrytis, shothole, fungal leaf spots, blackspot,white rot or sooty mould.

Thus, in a further aspect there is provided a method for controlling oralleviating the presence of microorganisms at a locus, which methodcomprises applying thereto an effective amount of a compositionaccording to the invention. Preferably, those microorganisms are presenton an animal and which are responsible for any of Contagious PustularDermatitis (Orf), footrot, digital dermatitis, or foul of the foot,scald or ringworm in any of said ungulate animals. As aforementioned,the composition may be applied in the form of a spray or in the case ofhoof associated conditions, as a foot bath as appropriate.Alternatively, the microorganisms may be present on plants or storedcrops or foodstuffs causing plant diseases such as moulds, rusts ormildew, including white blister, powdery mildew, downy mildew, greymould/botrytis, shothole, fungal leaf spots, blackspot, white rot orsooty mould.

The term “microorganism” as defined herein should be taken to mean anybacterial, virus, fungi or single cellular/unicellular or proteinaceousagent capable of transmitting disease or symptoms thereof to an animalor mammal, a plant or foodstuff.

The present invention may be more clearly understood with reference tothe following examples of the invention which are provided purely by wayof example only.

EXAMPLE 1

A foot bath or spray for application to affected animals was prepared inany of 200 L, 100 L or 50 L batches as desired in accordance with thefollowing composition.

FUNG. FOOT SPRAY/BATH - FOR SHEEP/CATTLE 500 mls Spray 5 L bath 200 L100 L 50 L 40 × 5 L 20 × 5 L 10 × 5 L To Make 400 × 500 mls 200 × 500mls 100 × 500 mls Clove Bud 20 L 10 L 5 L Eucalyptus 33.5 L 16.75 L 8.4L Lavender 6.5 L 3.25 L 1.6 L Tea Tree 3.25 L′ 1.6 L 800 mls Orange Oil13.5 L 6.75 L 3.4 L Aqualose LL 3.25 L 1.6 L 800 mls 100 Surfacare 2.5 L1.25 L 630 mls Water 117.5 L 58.8 L 29.37 L1. Summary

On May 8, 2001 (Day 0), fifty 12 week old indoor reared Suffolk crossMule lambs were allocated to five groups of 10 animals following footscoring for Ovine Interdigital Dermatitis (OID). Groups were treatedwith Barrier Foot Bath or Barrier Foot Spray while the remaining 10lambs were left as untreated controls. Feet were scored on Day 0, 2, 7,9 and 14. Lambs were re-treated on Day 7. All treatments reduced thegroup foot score over the 14 day period compared to the untreatedcontrols.

2. Objective

To evaluate the efficacy of two Barrier Animal Health formulations(Barrier Foot Bath and Barrier Foot Spray) in a field situation againstscald (Ovine Interdigital Dermatitis or OID) in lambs against untreatedcontrols.

3. Materials and Methods

3.1 Site Details

The sheep were located at Roundhay Farm, Yardley Hastings, Northamptonand were housed throughout the trial. The building used was wellventilated and drained and lambs were stocked at approximately 1 m sqper lamb. They were bedded on dry straw. Proprietary creep pellets werefed ad lib from purpose built creep feed hoppers.

3.2 Animals

The trial was conducted on 50 Suffolk cross Mule lambs. They were bornin February and had been weaned off their mothers at approximately 7weeks of age. (This was due to movement restrictions imposed by FMD) Atthe start of the trial they were on average 12 weeks old and weighed inthe range 30–40 Kgs. The lambs had been housed since birth and scald wasidentified as a problem in a significant proportion of the group priorto the start of the trial. They had not been treated for scald in theprevious 14 days.

All lambs were in good health, (with the exception of lameness due toscald), throughout the trial. Each lamb was identified with anindividual numbered ear tag and the groups were subsequently marked withdifferent coloured spray marker on the neck. The lambs feet were cleanedand trimmed as necessary before scoring and subsequent treatment.

3.3 Inclusion Criteria

For inclusion in the trial, a lamb had to have at least one footaffected by scald. In addition, any lambs with feet that showed signs ofphysical damage or footrot were excluded from the trial.

3.4 Treatments

Lambs were tagged, their feet scored (see protocol at Appendix 1) andthen randomly allocated to one of the 5 groups. Each group was thenallocated to a treatment, 10 animals (40 feet) per group. Treatmentswere applied on May 8, 2001 (Day 0) between 1.15 pm and 2.15 pm andagain on May 15, 2001 (Day 7) between 12.30 pm and 1.30 pm. On eachoccasion feet were cleaned with water and trimmed as necessary beforetreatments were applied.

GROUP/COLOUR TREATMENT BATCH NUMBER 1 - Green None - untreated N/Acontrols 2 - Red Barrier Foot Bath 61050701 1:200 in water Exp May 01,2001 3 - Blue Formalin 5% - 107/1141 Strathclyde Nutrition Formaldehyde35%; methanol 10% 4 - Purple Barrier Foot Spray 62050701 Exp May 01,2002

All treatments were applied according to the manufacturers instructions.The footbath treatments were carried out in a polythene bath containing100 litres of water, giving an average depth of 55 mm to cover the wholefoot above the coronet. Both water and product were measured accuratelyinto the bath with calibrated containers.

3.5 Weather Conditions

The 8 May was relatively warm (15–18 Degrees centigrade) with a lightbreeze. There was some shade on site an the animals were not hetstressed at any time. On 15 May it was cooler and there had beenovernight rain.

3.6 Adverse Reactions

Observations after treatment confirmed there were no adverse reactionsimmediately after treatment in the Barrier Footbath, or BarrierFootspray nor were any reactions noted during the following 48 hours.However, in the 5% formalin treated group, the lambs with badly affectedfeet were in obvious discomfort afterwards. Several refused to put thebad foot down and take weight on it, most stood up against the wall withdrooped heads and ears. This lasted for 20–30 minutes, after which thereappeared to be no persistent effect.

3.7 Animals Removed from the Trial

No animals were removed from the trial. Four feet of score 4 had to beremoved from the control group on Day 2 because they were deterioratingfurther and welfare considerations demanded treatment.

3.8 Monitoring

The feet were scored ‘blind’ (i.e. group unknown at time of scoring) onall occasions (Day 0, Day 2, Day 7, Day 9 and Day 14).

3.9 Other Treatments

No other treatments were given to the lambs during the course of thetrial.

4. Results

For the purposes of analysis and discussion, the results have beencollated in two ways:

4.1 Total Foot Scores for Each Treatment Group

Table 1 shows the total foot score by group on Day 0, 2, 7, 9 and 14.These results demonstrate that all treatments had an effect on the totalfoot scores of the groups.

TABLE 1 TOTAL FOOT SCORE FOR EACH GROUP GROUP Day 0 Day 2 Day 7 Day 9Day 14 1 - Control 42 45 43 37 47 2 - Barrier 39 36 39 31 34 Foot Bath3 - 40 35 47 27 31 Formalin 5% 4 - Barrier 42 39 49 35 38 Foot Spray (*significant at p <= 0.01)

The barrier products reduced the incidence of the condition. Formalinfared only slightly better but caused significant pain to the animals.

5. Discussion and Conclusion

Therefore all treatments had a positive effect on group foot score,reducing the total score compared to the controls over the trial period.

EXAMPLE 2

Trials Commenced 1, Nov. 2000

Various grain feeds (untreated) were selected for trials which were tolast for 12 weeks. We diluted the Antimicrobial Composition and sprayedthe feed in exactly the same way as would have been done in their Mill.Currently AP201 ammonium propionate mould inhibitor (normally diluted1:10) is used on many feeds. It is sprayed at the final stages using afine mist directly to the feed as it is carried along a conveyor systemfor packing.

A total of eleven trials were carried out using different dilution ratesvarying from 1:10 to 1:200.

After we applied our composition, the feed was stored in warm and moistconditions. After 12 weeks, the samples were tested for the presence ofmoulds and the results are shown in Table 1. In this test 11 sampleswere used of the feed. 5 grams of each sample were reconstituted with 10ml of sterile recovery medium. 1 gram of the resulting suspension wasspread onto selective mould enhancing growth medium and incubated at 22°C. for 6 days. The trials had to be carried out over a twelve weekperiod as that is the length of time feed manufacturers would like thefeed to remain mould free.

Plant Protection

The same antimicrobial composition was tested on various moulds between1, Apr. 2001 and 15, Jul. 2001. We tested the composition—diluted 20 mlsin 10 L water and applied the mixture to 38 various Roses, which weresuffering with Powdery Mildew. The sites were at Snetterton and Eastonwhere we found several affected bushes and climbers.

We were very surprised at the speed in which the plants recovered. Sixweeks after application, none of the plants showed signs of Mildew.

We went on to test the same product on fruit trees which included apple,pear, cherry and plum. The trees were affected with Bacterial Leaf Spotsand Rusts. We removed the affected leaves and applied our formula to thepoint of run off to all of the green foliage. Four weeks later there wasabsolutely no sign of Leaf Spots or Rust returning and all of the treeswent on to fruit very well.

Throughout the entire summer, many other plants including trees, shrubs,bulbous plants, vegetables and indoor plants were tested and on everyoccasion, the formula seemed to work very well were any type of fungiexisted. It also seemed to prevent new fungi developing for around 12weeks.

TABLE 1 Sample Mould c.f.u. per gram sample A <1 B <1 C <1 D <1 E <1(1:50 dilution) F <1 G <1 H  4 (1:50 dilution) J <1 K <1 L 20 (1:200dilution)

1. A composition comprising, by volume, 16–36% clove bud oil, 34–54%eucalyptus oil, 3.5–13.5% lavender oil, 2–6% tea tree oil and 17.5–27.5%orange oil wherein the volume percentages are based upon total volume ofthe composition.
 2. A composition according to claim 1 furthercomprising a thickening agent.
 3. A composition according to claim 2wherein said thickening agent is lanolin.
 4. A composition according toclaim 3 comprising, by volume, 16–36% clove bud oil, 34–54% eucalyptusoil, 3.5–13.5% lavender oil, 2–6% tea tree oil, 17.5–27.5% orange oiland 2–6% lanolin.
 5. A composition according to claim 4 which is furtherdiluted with water.
 6. An antimicrobial composition comprising, byvolume, 5–15% clove bud oil, 10–23.5% eucalyptus oil, 1–6% lavender oil,0.5 to 2.5% of tea tree oil, 3–9.5% orange oil, 0.5%–2.5% lanolin,0.5–2.0% surfactant and 40–80% water wherein the volume percentages arebased upon total volume of the composition.
 7. A composition accordingto claim 6 wherein said lanolin is Aqualose LL100.
 8. A compositionaccording to claim 6 wherein said surfactant is polyoxyethylene which isSurfacare T20.
 9. A composition according to claim 1 which is dilutedfurther prior to application.
 10. A composition according to claim 1which is formulated for application as a spray.